The Ephthalite war, which compelled Kobad to make peace with Anastasius, appears to have occupied him uninterruptedly for ten years. During its continuance Rome took advantage of her rival’s difficulties to continue the system (introduced under the younger Theodosius) of augmenting her own power, and crippling that of Persia, by establishing strongly fortified posts upon her border in the immediate vicinity of Persian territory. Not content with restoring Theodosiopolis and greatly strengthening it defences, Anastasius erected an entirely new fortress at Daras, on the southern skirts of the Mons Masius, within twelve miles of Nisibis, at the edge of the great Mesopotamian plain. This place was not a mere fort, but a city; it contained churches, baths, porticoes, large granaries, and extensive cisterns. It constituted a standing menace to Persia; and its erection was in direct violation of the treaty made by Theodosius with Isdigerd II., which was regarded as still in force by both nations. We cannot be surprised that Kobad, when his Ephthalite war was over, made formal complaint at Constantinople (ab. A.D. 517); of the infraction of the treaty. Anastasius was unable to deny the charge. He endeavored at first to meet it by a mixture of bluster with professions of friendship; but when this method did not appear effectual he had recourse to an argument whereof the Persians on most occasions acknowledged the force. By the expenditure of a large sum of money he either corrupted the ambassadors of Kobad, or made them honestly doubt whether the sum paid would not satisfy their master.